The structure of trans-[CrCl(2)(Me(2)tn)(2)]Cl (Me(2)tn=2,2-dimethylpropane-1,3-diamine) has been determined by a single-crystal X-ray diffraction study at 150K. The analysis reveals that there are two independent Cr(III) complex cations in the structure, one with crystallographic inversion symmetry and the other with two-fold rotation symmetry, which are conformational isomers of each other. In both conformations, the chromium atom adopts a distorted octahedral structure with the four nitrogen atoms of two Me(2)tn ligands occupying the equatorial plane and two chlorine atoms occupying trans-axial positions. The six-membered chelate rings are in stable chair conformations with N-Cr-N angles of 87.03(8) degrees and 88.99(8) degrees . The two chelate rings in the centrosymmetric complex cation 1 are anti, while those in the rotation-symmetric complex cation 2 are in syn conformations. The mean Cr-N and Cr-Cl bond lengths are 2.0922 and 2.3253 A, respectively. The infrared and UV-visible absorption spectra of trans-[CrCl(2)(Me(2)tn)(2)]Cl have also been measured. The resolved band maxima of the electronic d-d spectrum are fitted with a secular determinant for a quartet energy state of the d(3) configuration in a tetragonal field including configurational but neglecting spin-orbit coupling. It is confirmed that the nitrogen atoms of the Me(2)tn ligand have a strong sigma-donor character, but the chloro ligand has weak sigma- and pi-donor properties toward the chromium(III) ion.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.saa.2007.01.002 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In-situ engineering of centralized mesopores and edge nitrogen for porous carbons toward zinc ion hybrid capacitors.
J Colloid Interface Sci
January 2025
School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, Guangxi University (GXU), 100 Daxuedong Road, Xixiangtang District, Nanning 530004 China. Electronic address:
Porous carbons with large surface area (>3000 m/g) and heteroatom dopants have shown great promise as electrode materials for zinc ion hybrid capacitors. Centralized mesopores are effective to accelerate kinetics, and edge nitrogen can efficiently enhance pseudocapacitive capability. It is a great challenge to engineer centralized mesopores and edge nitrogen in large-surface-area porous carbons.
View Article and Find Full Text PDFEvaluation of SB-83, a 2-amino-thiophene derivative, against Leishmania species that cause visceral leishmaniasis.
Int Immunopharmacol
January 2025
Infectious Diseases Laboratory, Campus Ministro Reis Velloso, Federal University of Parnaíba Delta, 64202-020 Parnaíba, PI, Brazil. Electronic address:
Visceral leishmaniasis is a systemic disease that affects various internal organs and represents the most severe and fatal form of leishmaniasis. Conventional treatment presents significant challenges, such as prolonged management in hospital settings, high toxicity, and an increasing growing number of cases of resistance. In previous studies, our research group demonstrated the effective and selective activity of the 2-amino-thiophene derivative SB-83 in preclinical models of cutaneous leishmaniasis.
View Article and Find Full Text PDFUnveiling the electrochemical nitrogen reduction reaction mechanism in heteroatom-decorated-MoCS-MXene: the synergistic effect of single-atom Fe and heteroatom.
Mater Horiz
January 2025
Institute of Biomass Engineering, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, 510642, China.
Conversion of nitrogen (N) to ammonia (NH) is a significant process that occurs in environment and in the field of chemistry, but the traditional NH synthesis method requires high energy and pollutes the environment. In this work, the charge, orbital and spin order of the single-atom Fe loaded on heteroatom (X) doped-MoCS (X = B, N, O, F, P and Se) and its synergistic effect on electrochemical nitrogen reduction reaction (eNRR) were investigated using well-defined density functional theory (DFT) calculations. Results revealed that the X-element modified the charge loss capability of Fe atoms and thereby introduced a net spin through heteroatom doping, resulting in the magnetic moment modulation of Fe.
View Article and Find Full Text PDFProduction of Organic Precursors via Meteoritic Impacts and Its Implications for Prebiotic Inventory of Early Planetary Surfaces.
Astrobiology
January 2025
NASA Goddard Space Flight Center, Greenbelt, Maryland, USA.
Meteoritic impacts on planetary surfaces deliver a significant amount of energy that can produce prebiotic organic compounds such as cyanides, which may be a key step to the formation of biomolecules. To study the chemical processes of impact-induced organic synthesis, we simulated the physicochemical processes of hypervelocity impacts (HVI) in experiments with both high-speed C projectiles and laser ablation. In the first approach, a C beam was accelerated to collide with ammonium nitrate (NHNO) to reproduce the shock process and plume generation of meteoritic impacts on nitrogen-rich planetary surfaces.
View Article and Find Full Text PDFActivity and stability origin of core-shell catalysts: unignorable atomic diffusion behavior.
Chem Sci
January 2025
Interdisciplinary Research Center for Sustainable Energy Science and Engineering (IRC4SE2), School of Chemical Engineering, Zhengzhou University Henan 450001 China
The exceptional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performances of core-shell catalysts are well documented, yet their activity and durability origins have been interpreted only based on the static structures. Herein we employ a NiFe alloy coated with a nitrogen-doped graphene-based carbon shell (NiFe@NC) as a model system to elucidate the active structure and stability mechanism for the ORR and OER by combining constant potential computations, molecular dynamic simulations, and experiments. The results reveal that the synergistic effects between the alloy core and carbon shell facilitate the formation of Fe-N-C active sites and replenish metal sites when central metal atoms detach.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!